I found that I can move my P6 repaints from SS06 to SS08. the P6 is found here in SS08:
C:\Program Files\Vstep\ShipSim2008\Actors\Objects\Harbour Patrol\001 rotterdam autorities
Rename the Act_P6_Port_authorities_Custom_Police.dds to something else to save the file, then copy your .dds file of your repaint from SS06 and viola! your custom paint job is now in SS08!
WW